The invention concerns a hose clamp for fastening a hose received over a connecting piece, where the hose clamp has a tightening ring or band at least partially surrounding the hose and a clamping element cooperating with the ends of the tightening ring.
Hose clamps are used to fasten a hose to a hose nozzle, a connector fitting or the like. Hose clamps of this type are made, for example, of wire or strip material. Typically, the clamping element joins together the two ends of the wire or the strip in a manner such that the hose clamp may be tightened. Thus it is known to provide the strip material with toothing resembling a toothed rack and to provide a clamping element in the form of a screw. A screw of this type is generally received by a corresponding holder; it cooperates with the second end of the strip which resembles a toothed rack. The screw can be tightened (or released) by rotating the screw with a tool. Another proposal (DE-GM 84 15 973.1) describes a wire ring which only partially surrounds the connecting piece, and which is equipped with two lugs through which a screw is passed. The screw freely turns in one lug and cooperates with the other lug in the manner of a nut. The space between the two outwardly bent lugs is covered by a slide comprising corresponding portions on both sides. This slide is necessary to cover the space between the outwardly bend lugs so as to prevent introduction of folds as the hose is squeezed during its tightening. As a rule, such tightening rings can be mounted in the open state only and must be initially brought into a position for tightening after their application to the hose. This means that either the end of the strip must be threaded into a guide of the screw or the tightening screw must be fitted into the second lug serving as the nut. Furthermore, the manufacture of such hose clamps is expensive, as different single pieces must be made and in part further processed. The mounting of such hose clamps by automatic devices is generally impossible.